Patents Examined by Cathy F. Cam
  • Patent number: 5981043
    Abstract: The invention provides a conductive, flexure-resistant electromagnetic-shielded flexible printed circuit assembly obtainable by forming a copper foil circuit on a heat-resistant plastic film, disposing successively thereon an undercoat layer, a metal-powder-containing electromagnetic paste shield layer and an overcoat layer, with the ground pattern of the copper foil circuit being electrically connected to the above shield layer through the undercoat layer at appropriate intervals.
    Type: Grant
    Filed: December 17, 1997
    Date of Patent: November 9, 1999
    Assignee: Tatsuta Electric Wire and Cable Co., Ltd
    Inventors: Hisatoshi Murakami, Shinichi Wakita, Tsunehiko Terada, Shohei Morimoto
  • Patent number: 5900675
    Abstract: An integrated circuit chip package with an integrated chip carrier having differing coefficients of thermal expansion (CTE) in the x-y plane. The chip carrier is comprised of two main regions. The first is a core region having a CTE approximately equal to that of the semiconductor chip CTE. This core region also has approximately the same dimensions in the x-y plane as the semiconductor chip. The chip is mounted just above this core region. The second region is a peripheral region which surrounds the core region in the x-y plane. This second region has a CTE approximately equal to that of the printed circuit board CTE. During thermal cycling, the materials expand and contract. The core region expands at nearly the same rate as the chip and the area outside the chip footprint, the peripheral region, expands at a rate similar to that of the printed circuit board. This characteristic prevents thermal stress-induced fatigue on the package components and solder joints.
    Type: Grant
    Filed: April 21, 1997
    Date of Patent: May 4, 1999
    Assignee: International Business Machines Corporation
    Inventors: Bernd Karl-Heinz Appelt, Donald Seton Farquhar, Robert Maynard Japp, Konstantinos I. Papathomas
  • Patent number: 5733639
    Abstract: A laminated circuit board comprising a high frequency, low dielectric, and low dissipation factor foam substrate layer and at least one metal cladding layer laminated to the foam substrate layer. The foam substrate layer is formed of a closed-cell polyisocyanurate rigid foam having a closed-cell structure greater than 95%.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: March 31, 1998
    Assignee: Poly Circuits/M-Wave
    Inventor: Daniel T. Gosselin